Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVE-2026-44635
Summary
Kysely 0.28.12 added a `sanitizeStringLiteral()` call inside `DefaultQueryCompiler.visitJSONPathLeg` (commit 0a602bf, PR #1727) to fix CVE-2026-32763 (GHSA-wmrf-hv6w-mr66). The fix only doubles single quotes (' - ''); it does not escape JSON-path metacharacters (., [, ], *, **, ?). When attacker-controlled input flows into `eb.ref(col, '->$').key(input) or .at(input)` -- including type-safe code where the JSON column is shaped like `Record<string, T>` so K extends string is the inferred type -- every dot becomes a path-leg separator, letting an attacker traverse from the intended key into sibling and child fields the developer never meant to expose. The result is read access (and, in update statements, write access) to JSON sub-fields outside the intended scope across MySQL, PostgreSQL and SQLite.
- LOW
- NETWORK
- NONE
- UNCHANGED
- NONE
- NONE
- HIGH
- NONE
CWE-22 - Path Traversal
Path traversal (or directory traversal), is a vulnerability that allows malicious users to traverse the server's root directory, gaining access to arbitrary files and folders such as application code & data, back-end credentials, and sensitive operating system files. In the worst-case scenario, an attacker could potentially execute arbitrary files on the server, resulting in a denial of service attack. Such an exploit may severely impact the integrity, confidentiality, and availability of an application.
Advisory Timeline
- Published
